A June 12, 2007, segment on The O'Reilly Factor addressed a recent lawsuit filed by a gay woman against online matchmaker eHarmony.com. (She's suing the company for discrimination because they do not offer matchmaking services for homosexuals.)
In the segment, lawyer Sunny Hostin stated that, due to California law, the lawsuit may have merit, even though eHarmony.com is a private company. She then opined that eHarmony could be missing out on a lot of money from "10 percent of the population" by negating homosexuals.
Well, although the line is still commonly heard today, the "10 percent" figure has been debunked. Even the homosexual community has admitted the figure is false. A Friend of the Court brief filed with the 2003 Lawrence v. Texas Supreme Court case said that a National Health and Social Life Survey ("the most widely accepted study of sexual practices in the United States," according to the brief) reported "that 2.8% of the male, and 1.4% of the female, population identify themselves as gay, lesbian, or bisexual." (source).
In other words, it's not "10 percent."